Abstract:

Objective: To investigate the clinical characteristics of patients with non-tuberculous mycobacterial (NTM) spondylitis, aiming to enhance the quality of clinical diagnosis and treatment. Methods: A retrospective analysis was conducted on the clinical data of 12 patients with NTM spondylitis who underwent surgical treatment at the Department of Orthopedics, Beijing Chest Hospital Affiliated with Capital Medical University, the Fourth People’s Hospital of Qinghai Province, and Harbin Chest Hospital Affiliated with Harbin Medical University, from January 2023 to September 2024. The analysis included patient demographics, clinical symptoms and signs, lesion location, pre-admission diagnosis and treatment, laboratory and imaging findings, drug treatment regimens, surgical interventions, prognosis, and follow-up outcomes. Results: All 12 patients with NTM spondylitis had one or more underlying conditions or diseases associated with immunosuppression. The time from disease onset to diagnosis ranged from 12 to 24 months. Among these patients, 8 had received anti-tuberculosis treatment for 1 year or more, while 4 had undergone such treatment for 6 to 9 months. Three patients underwent MGIT 960 liquid culture, with only 1 patient subsequently tested for TB-DNA. Next-generation sequencing (NGS) was performed on 5 patients, pathological DNA diagnosis on 2 patients, and combined NGS and pathological DNA characterization on 2 patients. Ultimately, 8 different NTM species were identified, predominantly including the M.avium complex, M.intracellulare, and M.abscessus complex. Preoperative anti-NTM treatment consisted of a 6-week regimen for 7 patients, an 8-week regimen for 4 patients, and a 4-week regimen for 1 patient with concurrent pulmonary infection. Among these patients, 3 underwent posterior-only surgical intervention, while 1 patient received anterior-only surgery due to severe bone destruction. Of the 8 patients who required reoperation, 5 underwent combined anterior and posterior procedures, 1 had anterior-only surgery, and 2 underwent sinusectomy. Three patients required a third-stage operation or an additional sinusectomy. Postoperative anti-NTM therapy and rehabilitation training were maintained for 8 to 12 months. At the 2-year follow-up, 8 patients achieved complete recovery, while 4 patients continued to have sinus tracts or residual cavities, including 1 patient who ceased treatment after undergoing 7 surgical procedures. Conclusion: NTM spondylitis often presents with a clear history of occupational exposure and diverse infection strains, frequently resulting in long-term misdiagnosis and inappropriate treatment due to insufficient strain identification, thereby prolonging the disease course. Pathological and molecular biological testing can facilitate definitive diagnosis. Surgical intervention is the primary treatment for patients with chronic disease progression and severe spinal damage, achieving a cure rate of approximately two-thirds but carrying a significant risk of reoperation. Therefore, accurate identification of the causative pathogens and timely preoperative diagnosis are essential. Adequate and targeted anti-NTM therapy should be administered promptly to minimize the risk of postoperative sinus formation and abscess exacerbation, ensuring favorable surgical outcomes.

Key words: Spondylitis, Atypical bacteria, Mycobacterium, Disease characteristics, Treatment outcome